Newly recorded species of Gomphonema from the Hengduan Mountains in China

This paper reports 18 new records of diatoms from the genus Gomphonema in the Hengduan Mountains of China, including G. intricatum var. capitata Hustedt, G. angustius Reichardt, G. afrhombicum Reichardt, G. pseudointermedium Reichardt, G. auguriforme Levkov, G. californicum Stancheva & Kociolek, G. sublaticollum Reichardt, G. sphenovertex Lange-Bertalot & Reichardt, G. wiltschkorum Lange-Bertalot, G. vardarense Reichardt, G. parvuliforme Lange-Bertalot, G. parvuloides Cholnoky, G. lacus-victoriensis Reichardt, G. yucatanense Metzeltin & Lange-Bertalot, G. angusticephalum Reichardt & Lange-Bertalot, G. lange-bertalotii Reichardt, G. intermedium Hustedt, and G. medioasiae Metzeltin, Lange-Bertalot & Nergui. Detailed descriptions of the morphological characteristics, geographical distribution, habitat preferences, and physicochemical indices for each species are provided. Furthermore, comparative analyses of the morphological characteristics of the newly recorded species and their closely related counterparts are discussed.